<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script src="https://unpkg.com/vue@next"></script>
    <div id="app">
        <input v-focus>
    </div>

    <script>
        const vueOpt = {
            data(){
                return {
                    
                }
            }
        }

        const app = Vue.createApp(vueOpt);

        app.directive('focus', {
            mounted(el){
                el.focus()
            }
        })

        app.mount('#app');

    </script>
</body>
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